James the best answer is a definite maybe.  I don't quite understand the terminology you are using - "activities of the products".

I do understand a little bit (I think) if what you're trying to do. One of my former partners had a lawn care service.  The reason I recommended the Work Order Seminar.

With Access you can be as simple or as granular as you need to be.
Thing is I would combine all of your items in to one table that you are selling.
Whether you invoice for 1 Application or 3 hours of labor / application.  The next line item might be 4 lbs 10-10-10 poultry fert. The next might be mowing,  10K sq/ft  Understand?
The products and services can be broken out how ever you need but all the "items" you offer go in your products table whether it's widgets or services.

Then down the line you can go back through, using reports, to show the items you need to track.
You has x hours of labor, used y lbs. of pre-emergent, z gals of ground clear.  And so on.

Check out the Chef's Kitchen Helper video.   It might help you to think outside the box a bit.
Apply the things you use and do to making a recipe.  

Also look at the {1515} if you haven't already.

Invoicing

Hi James. It's always hard trying to help someone who isn't a student that's taken my courses. You're a Gold Member, which is wonderful. Welcome. But I have no idea what you know. With my regular students, I know if they've taken the Beginner courses, Expert courses, etc. So... I'll just tell you how I would set it up. ONE table for products. I'm assuming you sell chemicals, fertilizers, and then the service to apply them and do "other stuff" which would be activities. Why not put them all together in one product table? I used to sell computer hardware, software, and service. Whether it was a motherboard, an hour of training, or performing scheduled maintenance on a PC, it was all a "product" in my database. Unless you have a specific reason to split them into multiple tables... don't. But that's just my two cents. I also have other databases like my Work Order Seminar where I do split service and products into separate tables.

The major benefit of using Access instead of some off-the-shelf software is you can build it however you like. Whatever works best for you and your business needs.

Awesome, thank you guys for your time and help on this...

Hey Guys, I am wondering if I have assigned a piece of out to an employee or crew. How can I do this correctly, Code, wise. To assign it In and Out to an Employee or Crew.

Just another table with employee ID, in and out dates.